Humans continually learn relationships between the tasks they perform during their daily routines and the context in which the tasks are executed. The chief concern of the proposed research regards how these learned relationships are capitalized upon to influence behavior. In particular, this project aims to examine how contextual information from the visual environment impacts how attentional set--a preparatory state of the visual system that prioritizes the selection and inspection of visual information based upon a defining characteristic of the target (e.g., red or vertical)--is implemented and reconfigured. An initial approach seeks to determine if, and how, the implementation of an attentional set can be automatically triggered by an implicitly learned visual context. A second approach will probe the role of context in the reconfiguration from one attentional set to another. A third approach seeks to examine the neural mechanisms underlying context-driven set reconfiguration. To explore these questions, behavioral experiments and functional magnetic resonance imaging (fMRI) will be carried out with normal human subjects.